1. Field of the Invention
The present invention relates to an electrical connector for electrically connecting an electronic package such as a central processing unit (CPU) with a circuit substrate such as a printed circuit board (PCB), and particularly to an electrical connector having an enhanced base structure.
2. Description of Prior Art
Electrical connectors are widely used in personal computer (PC) systems for electrically connecting electronic packages such as CPUs with circuit substrates such as PCBs. Typical such electrical connectors are known as CPU sockets. A typical CPU socket comprises a base soldered and electrically connected with a PCB, a cover slidably mounted on the base and having a CPU attached thereon, and an actuation device for actuating the cover to slide along the base.
The CPU has a plurality of lead pins depending from a bottom surface thereof and arranged in a rectangular array. The cover of the CPU socket has a plurality of through holes arranged in a rectangular array corresponding to the lead pins of the CPU. The base of the CPU socket has a plurality of receiving passageways arranged in a rectangular array corresponding to the lead pins of the CPU. Each receiving passageway receives an electrical terminal therein.
In use, the CPU is attached to the CPU socket. The pins of the CPU extend through the corresponding through holes of the cover and are received in the corresponding passageways of the base. The pins of the CPU do not contact the corresponding electrical terminals. Thus the CPU is attached on the CPU socket with zero insertion force. In particular, the pins of the CPU are prevented from being flexed by sudden force being applied thereto by the electrical terminals. Then, the actuation device actuates the cover to slide along the base. When the cover reaches a closed position with respect to the base, the actuation device pushes the pins of the CPU into mechanical and electrical engagement with the corresponding electrical terminals.
This kind of conventional CPU socket is detailed in xe2x80x9cDevelopment of a ZIF BGA Socketxe2x80x9d (Connector Specifier Magazine, May 2000). Similar kinds of CPU sockets are also disclosed in U.S. Pat. Nos. 6,280,223, 6,368,137, 6,371,785, 6,338,639 and 6,406,317.
The base of the conventional CPU socket generally defines a receiving space at one end thereof. A quadrate hole is defined in a bottom wall of the receiving space. The bottom wall of the receiving space is relatively thin, and stress on four right angles of the quadrate hole is relatively large during manufacturing. Thus, the bottom wall at the right angles is prone to distort when the actuation device is assembled into the base. Furthermore, when molding the base during manufacturing, melted plastic material cannot fully fill a region of the base at the quadrate hole, especially at the right angles of the quadrate hole. This results in a thickness of the bottom wall at the receiving space being uneven.
In view of the above, a new electrical connector that overcomes the above-mentioned disadvantages is desired.
Accordingly, an object of the present invention is to provide an electrical connector for electrically connecting an electronic package such as a central processing unit (CPU) with a circuit substrate such as a printed circuit board (PCB), in which the connector has an enhanced base structure that provides the connector with uniform dimensions and enhanced intension during manufacturing.
To achieve the above-mentioned object, an electrical connector in accordance with a preferred embodiment of the present invention is for electrically connecting a CPU with a PCB. The electrical connector comprises an insulative base, a cover, and an actuation device for actuating the cover to slide along the the base. The base defines a plurality of receiving passageways respectively receiving corresponding electrical terminals therein. The cover defines a plurality of through holes corresponding to the receiving passageways. The base further defines a receiving space at one end thereof. A circular hole is defined in a bottom wall of the base below the receiving space, which can ensure that the base at the receiving space has a uniform thickness and enhanced intension during manufacturing.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: